IRU1030-33
1
Rev. 1.1
06/29/01
TYPICAL APPLICATION
DESCRIPTION
The IRU1030-33 is a low dropout three-terminal fixed 3.3V
output regulator with minimum of 3A output current ca-
pability. This product is specifically designed to provide
well regulated supply for low voltage IC applications re-
quiring 3.3V output. The IRU1030-33 is guaranteed to
have <1.3V dropout at full load current
making it ideal to
provide well regulated output with supply voltage as low
as 4.6V input.
Guaranteed < 1.3V Dropout at Full Load Current
Fast Transient Response
1% Voltage Reference Initial Accuracy
Output Current Limiting
Built-In Thermal Shutdown
3A LOW DROPOUT POSITIVE
FIXED 3.3V REGULATOR
Tj (C) 3-PIN PLASTIC 3-PIN PLASTIC 2-PIN PLASTIC 2-PIN PLASTIC
TO-220 (T) TO-263 (M) Ultra Thin-Pak (P) TO-252 (D-Pak)
0 To 150 IRU1030-33CT IRU1030-33CM IRU1030-33CP IRU1030-33CD
Figure 1 - Typical application of IRU1030-33
TYPICAL APPLICATION
Data Sheet No. PD94125
5V
3.3V / 3A
C1
330uF
C2
330uF
IRU1030-33
1
2
3
Vout
Gnd
Vin
FEATURES
APPLICATIONS
Standard 3.3V Chip Set and Logic Applications
IRU1030-33
2
Rev. 1.1
06/29/01
ABSOLUTE MAXIMUM RATINGS
Input Voltage (Vin) .................................................... 7V
Power Dissipation ..................................................... Internally Limited
Storage Temperature Range ...................................... -65C To 150C
Operating Junction Temperature Range ..................... 0C To 150C
PACKAGE INFORMATION
3-PIN PLASTIC TO-220 (T) 3-PIN PLASTIC TO-263 (M) 2-PIN PLASTIC ULTRA THIN-PAK (P) 2-PIN PLASTIC TO-252 (D-Pak)
JT
=2.7
C/W
JA
=60
C/W
JA
=35
C/W for 1" Square pad
JA
=70
C/W for 1" Square pad
JA
=70
C/W for 0.5" Sq pad
PARAMETER
SYM
TEST CONDITION
MIN
TYP
MAX
UNITS
Output Voltage
Vo
Io=10mA,Tj=25!C,Vin=5V 3.267 3.300
3.333 V
Io=10mA, Vin=5V 3.234 3.300
3.366
Line Regulation
Io=10mA, 4.7V<Vin<7V
0.2
%
Load Regulation (Note 1)
Vin=5V, Vadj=0, 10mA<Io<3A
0.4
%
Dropout Voltage (Note 2)
Vo
Note 2, Io=3A
1.1
1.3
V
Current Limit
Vin=5V, dVo=100mV
3.1
A
Minimum Load Current
Vin=5V
5
10
mA
(Note 3)
Thermal Regulation
30ms Pulse, Vin-Vo=3V, Io=3A
0.01
0.02
%/W
Ripple Rejection
f=120Hz, Co=25F Tantalum,
Io=1.5A, Vin-Vo=3V
60 70 dB
Adjust Pin Current Change
Io=10mA, Vin-Vo=1.5V, Tj=25!C
0.2
5
A
Temperature Stability
Vin=5V, Vadj=0V,Io=10mA
0.5
%
Long Term Stability
Tj=125!C, 1000Hrs
0.3
1
%
RMS Output Noise
Tj=25!C, 10Hz<f<10KHz
0.003
%Vo
ELECTRICAL SPECIFICATIONS
Unless otherwise specified, these specifications apply over Cin=1F, Cout=10F, and Tj=0 to 150!C.
Typical values refer to Tj=25!C.
Note 3: Minimum load current is defined as the mini-
mum current required at the output in order for the out-
put voltage to maintain regulation. Typically the resistor
dividers are selected such that it automatically main-
tains this current.
Note 1: Low duty cycle pulse testing with Kelvin con-
nections is required in order to maintain accurate data.
Note 2: Dropout voltage is defined as the minimum dif-
ferential voltage between Vin and Vout required to main-
tain regulation at Vout. It is measured when the output
voltage drops 1% below its nominal value.
Tab is
Vout
Gnd
Vin
Vout
1
2
3
FRONT VIEW
Tab is
Vout
Gnd
Vout
Vin
FRONT VIEW
1
2
3
Gnd
Vin
Tab is
Vout
FRONT VIEW
1
3
Gnd
Vin
Tab is
Vout
1
3
FRONT VIEW
IRU1030-33
3
Rev. 1.1
06/29/01
APPLICATION INFORMATION
Stability
The IRU1030-33 requires the use of an output capacitor as part of the frequency compensation in order to make the
regulator stable. Typical designs for microprocessor applications use standard electrolytic capacitors with a typical
ESR in the range of 50 to 100m and an output capacitance of 500 to 1000F. Fortunately as the capacitance
increases, the ESR decreases resulting in a fixed RC time constant. The IRU1030-33 takes advantage of this
phenomena in making the overall regulator loop stable. For most applications a minimum of 100F aluminum
electrolytic capacitor such as Sanyo MVGX series, Panasonic FA series as well as the Nichicon PL series insures
both stability and good transient response.
Vin 3
1030-33blk1-1.0
1 Gnd
2 Vout
THERMAL
SHUTDOWN
CURRENT
LIMIT
1.25V
+
+
PIN # PIN SYMBOL
PIN DESCRIPTION
PIN DESCRIPTIONS
This pin must be connected to ground plane using a low inductance short connection.
The output of the regulator. A minimum of 10F capacitor must be connected from this pin
to ground to insure stability.
The input pin of the regulator. Typically a large storage capacitor is connected from this
pin to ground to insure that the input voltage does not sag below the minimum drop out
voltage during the load transient response. This pin must always be 1.3V higher than Vout
in order for the device to regulate properly.
BLOCK DIAGRAM
Figure 2 - Simplified block diagram of the IRU1030-33
1
2
3
Gnd
Vout
Vin
IRU1030-33
4
Rev. 1.1
06/29/01
Notes
IR WORLD HEADQUARTERS : 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105
TAC Fax: (310) 252-7903
Visit us at www.irf.com for sales contact information.
Data and specifications subject to change without notice. 02/01
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